Photographic developing table



March 28, 1961 w. l.A CHAMBERS 2,975,792

PHOTOGRAPHIC DEVELOPING TABnE Filed March .7, 195e FIG. /'2

WILLIAM L. CHAMBERS BY l ATTORNEYS United States Patent O PHOTOGRAPI-IIC DEVELOPING TABLE William L. Chambers, 461 S. Sycamore St.,

Ravenna, Ohio Filed Mar. 7, 1958, Ser. No. 719,828

7 Claims. (Cl. 9599) The present invention relates to the treating and processing of photographic paper and lm. More particularly, the invention relates to improved means for circulating various chemical solutions, as used for photographic developing, fixing, printing etc., over the sensitized surface of photographic papers or films.

The apparatus of the invention is primarily intended for use by the amateur photographer who develops and prints his own photographs. The purpose of the invention is to provide improved means whereby the amateur photographer, with a minimum of technical knowledge and experience, can develop and print photographs having a quality heretofore obtainable only by the use of expensive professional-type equipment.

Assuming that the photograph negative has been made on a proper lm with a correct amount of exposure, the amateur photographer most often goes astray during one of the several operations which require immersion and washing of the film or paper in various chemical solutions. The reaction between the sensitized film surface and the chemical solution requires that there be substantial agitation and movement of the solution relative to the sensitized surface. Further, such agitation must be substantially constant or unvarying and must result in uniform treatment of the entire surface area of the film. Otherwise, the density, contrast or grain of the resultant photograph will vary yand be non-uniform.

Itis therefore an object of the present invention to provide an improved means for contacting and treating the sensitized surface of photographic papers or films with chemical solutions. More particularly, it is an object to provide improved apparatus for constantly circulating a chemical'solution in a container over the sensitized surface of a photographic film or paper immersed in the solution, for uniform treatment of the entire surface area of the film.

These and other objects of the invention, as well as the advantages thereof over prior art apparatus and techniques, will be apparent from the following detailed description taken with the attached drawing.

-In the drawing:

Fig. 1 is a view of a conventional solution tray supported on apparatus according to the invention;

Fig. 2 is a section taken substantially on line 2-2 of Fig. 1; and

Fig. 3 is an enlarged section taken substantially on line 3-3 of Fig. 1..

A form of apparatus -according to the invention is indicated generally at 10. The apparatus may be used with a container or tray indicated at 12. The tray 12 as shown is a conventional type having a rectangular bottom 13, sloped sides 14 and a pouring lip 15. The tray 12 is partly filled with a suitable chemical solution S and a Patented Mar. 28, 1961 table 18 has a stud 20 depending therefrom and attached thereto as by a screw 21. The stud 20 is formed of a suitable wear-resistant material and is journaled in a hub bearing 22. The bearing 22 is pressed in a bore extending vertically through a hub 24 located at the center of a table support 25.

Referring to Fig. 2, the support 25 is a preferably rectangular box-like structure. In addition to the rotatable table mounting provided by stud 20 and bearing 22, each corner of the table 18 is permitted limited movement substantially circumferentially of stud 20 by bearing means indicated `at 26, Each bearing means includes an upper plate 27 attached to the under side of the table 18 substantially transversely of an imaginary line extending diagonally of the table through the center bushing 20. Each plate 27 has a groove or race 28 extending circumferentially of said stud 20. A lower plate 29 similar to plate 27 and also having a groove or race 28' is attached to the upper surface of the support 25. The opposed plates 27 and 29 rollably engage a ball or bearing 32 between them, within a substantially arcuate raceway defined by the upper and lower respective grooves 28 and 28 which extend circumferentially of the stud 20.

The table 18 is pivotally oscillated relative to the support 25 at any desired frequency by a suitable drive means including a conventional high torque fractional horse power electric motor 35, fastened by brackets 36 to the underside of the support. The output shaft 37 of the motor preferably is fitted with a bushing or frictional drive roller 38. The roller 38 engages a larger roller 39 mounted around a hub 40 journaled at its lower end in plate 36. The upper end of the hub 40 eccentrically engages one end 40 of a crank arm 41, as by an offset pin 42. The other end of the crank arm 41 has a pin 43 extending upwardly and journaled within a crank bushing 44 on the under surface of the table 18.

As shown, the table drive is located adjacent one edge thereof. Tnis position will provide a high or maximum extent of solution circulation. However, if desired the table drive elements could be moved nearer to the center bushing 20 to provide a lesser extent of solution circulation.

Referring to Fig. l, the circular arrows represent generally one movement of solution S within the tray 12 in response to the driving action of the crank arm 41. Within each corner quadrant of the tray, the solution flow is generally spiral. Each spiral or vortex extends into the center area of the tray, generally above the bushing 20. Referring to the upper left hand corner quadrant of tray 12, the wriggled arrows indicate additional currents set in motion by the crank arm 41 and which are substantially `linear and extend from either side of each corner and through the spiral or vortex current in each quadrant.

The circulation or movement of the solution S in a rectangular tray 12 may be regarded as taking place substantially in, or as being generally localized within, the four quadrants of the tray; each` quadrant including a combination of spiral and linear currents. Along the boundaries of each quadrant and at their apex, above bushing 20, the individual currents meet. It may thus be seen that the flow of solution S over the surface of the sheet 16 will be uniform. Further the rate of agitation will be constant varying only in the extent of time and thus a successive number of sheets 16 can be immersed in the tray 12 and each will receive the same uniform treatment and contact with solution S.

What is claimed is:

1. Apparatus for treating a sheet of photographic paper immersed in a chemical solution comprising, a rectangular container for said solution, a rectangular table having a top surface for supporting said container, a support underlying said table having means rotatably supporting said table at its center, bearing means between said table and said support at each corner of said table, each saidtbearing means being movable substantially arcuately of said means rotatably supporting said table, and means mounted on said support for imparting pivotally oscillating move-v ment to said table.

2'. Apparatus fortreatinga sheet of photographic paper immersed in a chemical solution comprising, a rectangular container for said solution, a rectangular table having a top surface for supporting said container, asupport underlying said table having means rotatably supporting said table at its center, bearing means between said table and saidfsupport at each corner of said table, said bearing means beingk movable substantially arcuately of said means rotatably supporting said table to permit a limited pivotally oscillatory movement of said table about its center, and means mounted on said support for imparting pivotally oscillating movement to said table.

3. Apparatus for circulating a chemical solution in a rectangular container over the sensitized surface of a sheet of photographic paper, comprising, a rectangular table mounted on asupport by corner bearing means, said bearing means being movable only substantially transverselyof a diagonal of said table, and means for pivotally oscillating said table about its center whereby circulation of a liquid within said container is generally localized within the four quadrants of the container, each quadrant generating a combination of spiral and linear currents.

4. Apparatus for circulating a chemical solution in a rectangular container over the sensitized surface of a sheet of photographic paper, comprising, a rectangular table rotatably connected at its center to a support, bearing means between said table and support at each corner of said table, said bearing means being movable only circumferentially of the center of said table and drive means attached to said support for imparting motion to said table, whereby circulation of a liquid within said container is generally localized within the four quadrants of the container, each quadrant generating a combination of spiral and linear currents.

5. Apparatus for circulating a chemical solution in a rectangular container over the sensitized surface of a sheet of photographic paper, comprising, a table for supporting said container, a support underlying said table, means rotatably connecting4 said table with said support at the center of said table, a bearing race at each corner of said table extending substantially circumferentially of its center, bearing races on said support opposed to and aligned with each bearing race on said table, a bearing movable within each aligned pair of opposed bearing races, said bearings carrying said table, and drive means attached to said support-for imparting-pivotally oscillatory motion to said table.

6. Apparatus for circulating` a-chemical solution in a rectangular container over the sensitized surface of a sheet of photographic paper', comprising, a rectangular table for supporting said container, a support underlying said table, means rotatably connecting said.` table with said support at the center of said table, a bearing race at each corner of said table extending substantially circumferentially of its center, bearing races on said support opposed to and aligned with each bearing race on said table, a ball bearing movable within each pair of opposed bearing races, said bearingscarrying said table, and drive means attached to said support for imparting pivotally oscillatory motion to said table.

7. Apparatus for use in treating a sheet of photographic material immersed in a rectangular container of chemical solution, comprising, a rectangular table having a surface adapted for supportingV a container, a stud depending from the center of said table, a bearing race atA each corner of said table extending substantially circumferentially of said stud, a support underlyingsaid table having a bore `journaled ou said stud, a bearing race on said support aligned with each race on said table, a bearing betweeneach pair of so opposed races supporting said table, and means mounted on said support for pivotally oscillating said table.

References Cited in the le of this patent UNITED STATES PATENTS 2,140,438 Webster Dec. 13, 1938 2,793,010 Menken May 21, 1957 2,828,949 Paladino et al Apr. 1, 1958 FOREIGN PATENTS 334,137 Germany Mar. 10, 1921 

